Wilderness Survival May Be Hungrier Than You Think
Living Off The Land: Delusions and Misconceptions About Hunting and Gathering
By Ross Gilmore
Ah, living off the land. Thriving in the wilderness with the use of your skills. It is the ultimate goal of many bushcrafters and survivalists. Numerous posts have been written on forums about this subject, and as soon as one ends, another is started. Of course, actual evidence is rarely presented. We often fall back on positions such as “our ancestors did it, so clearly I can do it”, or “I was out last week and saw a bunch of cattails and barriers, so my food sources are secure”.
The problem is not made any better by so called experts in the field, who fuel the myth that they are feeding themselves in the wilderness. I vividly remember watching Andrew Price, host of A-Z of Bushcraft in one of the episodes, waking up in the morning, walking a few feet next to camp, gathering a few berries, and then turning the camera and saying “breakfast is served”. Ray Mears, aside from his excellent series, Wild Foods, has numerous instances where he gathers meager resources and then implies that his food requirement have been met. Of course, none of them ever bother to calculate or present actual caloric values, or discuss the long terms consequences. Similarly, people like Dave Canterbury, who discuss at length hunting in wilderness living conditions, never actually do the math of how much game has to be killed to justify the weight of that shotgun being carried, or whether the numbers would work out at all.
For the past year I have been attempting to gather some actual numbers on the subject, so we can have a more meaningful conversation about what it would take to sustainably feed a person in the wilderness, and consequently, what tools may be suited for the task. I must admit, I have been slacking with the project because of its tedious nature. Last week however, a reader referred me to a source related to the Chris McCandless post, which provided me with some of the information I was searching.
Samuel Thayer, author of the books Forager’s Harvest and Nature’s Garden, wrote an essay related to the starvation of Chris McCandles titles Into the Wild and other Poisonous Plant Fables. While much of the essay focuses on disproving theories of poisonous plants, the last section discusses actual caloric requirements for a person living in the wilderness, and what resources that would require.
So, let’s assume a scenario where a person will be going into the wilderness with the intention of living off the land. He will practice wilderness self-reliance, he will thrive in nature, and whatever other cliché you want to insert here. Let’s also assume for the moment that there are no hunting or fishing regulations that we have to comply with, and let’s assume that the person has all necessary equipment, including hunting and fishing tools. What would the person need to procure each day in order to live in a sustainable manner for a prolonged period of time?
Well, the first piece of the puzzle is the required calories. Citing Michele Grodner’s Foundations and Clinical Applications of Nutrition, Thayer calculates that a male who is physically active under wilderness living conditions would need approximately 3,300 calories per day. This number seems consistent with calculations done by long distance backpackers, who usually aim for a bit over 3,000 calories per day. So, to maintain one’s physical condition, and prevent weight loss, the person in question must consume about 3,300 calories each day. Of course, there are other nutritional requirements, but at a very basic level, to prevent death from starvation in the long run, this caloric minimum must be met.
The above caloric requirement for wilderness living should not be confused with accounts of short term survival, where a person stays in the wilderness, slowly losing body weight, until they are rescued. We have plenty examples like this from series like Survivorman, Naked and Afraid, etc. Those are not examples of sustainable hunting and gathering situations, and we should not have any delusions about the long term applications of such a starvation diet.
So, sticking with the 3,300 caloric requirement per day, what would it take to meet these caloric needs?
Sources of Calories
Meat
First let’s look at animal products, something to which I will jointly refer to in this post as “meat”, but should be understood to include both protein and fats. Meat can vary in caloric content anywhere from 40 calories per ounce for lean meat like squirrel and rabbit, all the way to 60 calories per ounce for very fatty meat like salmon. Using these numbers, we can roughly calculate the caloric value of each animal, and how much of it we would need to meet the our daily caloric requirements.
Red Squirrel: as Thayer calculates, at an average of 2.8 ounces of meat per squirrel (Michele Grodner’s Foundations and Clinical Applications of Nutrition), it would take 25 squirrels per day to meet the caloric requirements, or if also eating the internal organs and brain, about 16 squirrels per day.
Rabbit: at about 16 ounces of meat per rabbit (Michele Grodner’s Foundations and Clinical Applications of Nutrition), you would need about 4 of them per day, or 3 if eating all of the organs and brain.
Salmon: assuming you are catching Sockeye salmon, they average 6 pounds (96 ounces) (Kenai Peninsula Borough Commercial Fishing Industry State Records, 2012). Since salmon meat is rich in fat, we can assume 60 calories per ounce (USDA SR-21), which would mean one salmon would give you 5,760 calories, or a little under two days of food.
Clams: clam meat varies in caloric density from about 33 calories per ounce to about 42 calories per ounce. (Interstate Shellfish Sanitation Conference, 2013). To satisfy the required 3,300 calories per day intake, you would need about 5 pounds of clam meat per day (using 40 calories per ounce for the calculation). In order to get 5 pounds of clam meat, you would need about 320 medium size clams. For each ounce of meat, you need about 4 medium size clams. (Interstate Shellfish Sanitation Conference, 2013)
Raccoon: while many people would not eat raccoon meat due to its high content of parasites, it is technically edible. The meat is fatty, averaging about 72 calories per ounce. (USDA SR-21) The weight of raccoons varies widely from 10 to 25 pounds for adults. The average listed size is about 25 pounds for an adult. That should provide approximately 10 pounds of meat once it is gutted, skinned and deboned. At 72 calories per ounce, such a raccoon will provide about 11,520 calories. However, keep in mind that these numbers reflect the calories if the animal is cooked to preserve all of its nutrients. In order to make it more palatable, people usually cook raccoon meat to remove most of the fat. If you do that, the caloric content will drop significantly. Assuming you save all of the fat however, a 25 pound raccoon should provide sufficient calories for 3.5 days.
Turkey: a good size turkey will yield about 10 pounds of meat (160 ounces) when processed. The caloric value of processed turkey meat is about 45 calories per ounce (USDA SR-21). Therefore, a turkey will produce 7,200 calories in total, or a bit more than 2 days worth of caloric requirements.
Deer: a mature buck typically yields about 70 pounds of meat (1,120 ounces) (University of Wisconsin study 2006). Venison is a lean meat, with about 53 calories per ounce (USDA SR-21). The meat of a mature buck will therefore give you 59,360 calories, which will be sufficient for 18 days of food at the 3,300 calories per day requirement. If you are eating the internal organs as well, that will probably get pushed to about 20-21 days of food.
Black Bear: a large black bear will produce about 100 pounds of meat (1,600 ounces) once processed. Bear meat has about 43 calories per ounce. (USDA SR-21) So, a large black bear will give about 68,800 calories total. That would be sufficient calories to satisfy the caloric intake for 21 days.
The table below gives a general summary of the results. The numbers you see in the last column for animals needed each day to meet the caloric requirement, the number in parenthesis represents what is needed if internal organs are preserved and eaten as well as the meat.
MeatType of Animal / oz of Meat/Animal / cal/oz of Meat / Total cal/Animal / Animals/Day
Squirrel / 2.8 / 47 / 132 / 25 (16)
Rabbit / 16.8 / 47 / 790 / 4 (3)
Salmon / 96 / 60 / 5,760 / 0.57
Clams / 0.25 / 40 / 10 / 320
Raccoon / 160 / 72 / 11,520 / 0.29
Turkey / 160 / 45 / 7,200 / 0.46
Deer / 1,120 / 53 / 59,360 / 0.056 (0.05)
Black Bear / 1,600 / 43 / 68,800 / 0.047
Plants
Now, let’s move to plant sources.
Cattail Roots: cattail roots, will yield about 8 calories per ounce (USDA SR-21; Revedin, A., et al. Thirty thousand-Year-Old Evidence of Plant Food Processing, 2010). This means that about 413 ounces or 26.5 pounds of cattail flour would be needed to meet that daily caloric requirements.
It should be noted (as pointed out by a reader in one of the comments) that Table 2 of the above study, Thirty thousand-Year-Old Evidence of Plant Food Processing, 2010 provides that cattail (Typha) rhyzome flour contains 266 kcal/100g, or 75 calories per ounce. That is much higher than the 8 cal/oz provided by the USDA and other sources. It appears the difference occurs because that table speaks of the caloric value of already processed and cooked flour. The article specifies that “The flour would have undergone a multistep processing involving root peeling, drying, and finally grinding using specific tools. After this, the flour needed to be cooked to obtain a suitable and digestible food.” Cattail rhyzome contains large portions that are inedible, such as the spongy layer covering the rhyzome as well as the fibers from which you have to remove the starch. As such, the numbers don’t appear to be contradictory. You may very well have a caloric value of 25 kcal/100g (8 cal/oz) for cattail root and 266 kcal/100g (75 cal/oz) for processed cattail root flour where the outer casing has been peeled, the fibers have been removed, and the resulting starch cooked. In the table here I have used the number for unprocessed cattail root, and the quantity you would need to get the necessary calories.
Parsnips and Similar Wild Roots: according to Thayer, at approximately 23 calories per ounce (Michele Grodner’s Foundations and Clinical Applications of Nutrition), about 9 pounds would be needed per day to meet the daily caloric requirement of 3,300 calories.
Blueberries: again, according to Thayer, at about 16 calories per ounce (Michele Grodner’s Foundations and Clinical Applications of Nutrition), you would need 13 pounds of blueberries per day to meet your caloric requirements.
Lingonberries: at about 5 calories per ounce (USDA SR-21), you would need about 41 pounds of lingonberries to meet your daily caloric requirement.
Acorns: once processed into a flour, after leaching out the tannic acid acorns will provide about 110 calories per ounce (USDA SR-21). That would mean that 30 ounces, or a little under 2 pounds of acorn flour would be needed per day to satisfy the caloric requirements.
Burdock Root: at about 20 calories per ounce (USDA SR-21), you would need about 165 ounces, or 10 pounds of unprocessed burdock root to meet your daily caloric requirements. If cooked, a large amount of the water removed, the pounds one needs to consume may be significantly reduced, but would still constitute more than what a person can eat in a day.
PlantsType of Plant / cal/oz of Plant Material / Pounds Per Day Needed
Cattail Root (Unprocessed) / 8 / 26.5
Parsnips / 23 / 9
Blueberries / 16 / 13
Lingonberries / 5 / 41
Acorns (processed) / 110 / 2
Burdock Root / 20 / 10*
The above represent average numbers, both for the calories required per day, and the amount of food which must be consumed to provide those calories. Variations should be expected. Even so, it is evident that a person attempting to live alone off the land in the wilderness has a serious challenge on his hands. The amount of food required seems absurd, but as Thayer explains: “If this seems like a high volume of food, that’s because it is. We have sought, developed, cultivated, and become accustomed to calorie-dense foods for so long that most of us have never been without them. We’ve never had to eat food in volumes like this. When you realize that a stick of butter has as many calories as two and a half quarts of blueberries or seven pounds of broccoli, you can see why the innate human desire for calorie-rich, low-fiber food developed.”
Gathering
The gathering of food has become a great area of teaching for survival and bushcraft instructors. Unfortunately, much of the teachings create a false impression of what it actually takes to feed oneself through gathering of food in the wilderness. As Thayer also noted, many such instructors teach, or imply through their representations that a very small amount of food is needed for a person to sustainably live in the wilderness. Whether the misrepresentations are intentional, or due to lack of knowledge is hard to say, but the results are the same-people fail to realize how much food must be gathered to sustain a person long term.
We have to make a clear distinction between “edible” plants and “food”. Just because something can be eaten, does not mean that it contributes to your caloric requirements in any meaningful way. Many staples of bushcraft teachings, such as dandelions provide virtually no caloric value. You can easily starve to death with a stomach full of such plants. In fact, it is not unlikely that a person may spend more energy gathering edible plants, than the calories he will get from consuming them. To effectively gather food in the wilderness, one has to know not only what is edible, but also what provides meaningful calories.
From the plants available and listed in the above chart, not surprisingly acorns provide the highest nutrition. I imagine it will be similar for other nuts because of the high oil content. If processed correctly, a person can certainly provide enough food for himself using acorn flour. The other plants that are readily available, including the all too popular cattail and burdock roots, are far less than ideal when it comes to providing sufficient calories for a person attempting long term living. Not only would it be difficult to supply yourself with enough of the plant, but consuming such large quantities would be impossible. We should also keep in mind that the plants I have listed here are the ones with relatively high caloric value.
On that subject, Thayer writes with respect to Chris McCandless, “If he didn’t get any meat, couldn’t he just eat more lingonberries and get all his calories that way? Absolutely not. He would have needed to eat almost three gallons of lingonberries per day. He’d probably be vomiting before finishing the second quart. No matter how many lingonberries were available to him, his body would have only accepted them for a small portion of his caloric requirement. This doesn’t make lingonberries “poisonous”; the same is true of virtually every food, although the appropriate proportions vary… The concept that foods can be eaten only in appropriate quantities is taken so much for granted that, to my knowledge, it has never been given a name in the medical literature. I call it themaximum caloric proportion (MCP). Some foods have a very high MCP, such as milk, meat, and potatoes. They are easily digested and contain few antinutrients or toxins, thus they are suitable as dietary staples. Others, such as cabbage, rhubarb, and raspberries, cannot serve as staple foods and are only suitable to supply small portions of the diet.
As one travels north, there tends to be fewer plants with a high MCP; this is why hunter-gatherers from northern latitudes ate meat for the great majority of their calories.”
As a result, if you can not find the right plants and gather it on a large enough scale, or have simply missed the gathering season, one typically has to resort to meat for the majority of the required calories. So, let’s look at some of what is required in terms of providing sufficient calories through hunting and fishing.
Opportunity Cost of Hunting and Fishing
Before we look at specific examples, it is important to note that when we speak of hunting and fishing, activities which require that you bring specific equipment into the woods, we have to look not only at what you can successfully hunt, but also at the opportunity cost of that equipment. What I mean by that is that for each pound of equipment which you bring with you, you have to forego a pound of some other resource which you could have brought with you instead. Since we are assuming a person who is otherwise prepared for the wilderness, the most immediate opportunity cost is food. For each pound of gear that you bring, you have to leave behind a pound of food. So, when you bring a 7 pound rifle with you, you could have instead left it behind and brought 7 pounds of food. So, when we look at the equipment one may bring for such hunting, we have to see not only if it can get us any food, but also whether the food we can procure with it is more than the food that we could have brought with us had we not brought the equipment.